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The Fred Fish Collection 1.5
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ffcollection-1-5-1992-11.iso
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300-399
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ff321.lzh
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Planets
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julday.c
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C/C++ Source or Header
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1990-02-27
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479b
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29 lines
#include <math.h>
#define IGREG (15+31L*(10+12L*1582))
long julday(mm,id, iyyy)
int mm,id,iyyy;
{
long jul;
int ja, jy,jm;
void nerror();
if (iyyy == 0) nerror("JULDAY: there is no year zero.");
if (iyyy < 0) ++iyyy;
if (mm > 2) {
jy = iyyy;
jm - mm + 1;
} else {
jy = iyyy - 1;
jm = mm+13;
}
jul = (long) (floor(365.25*jy)+floor(30.6001*jm)+id+1720995);
if (id+31L*(mm+12L*iyyy) >= IGREG) {
ja = 0.01*jy;
jul += 2-ja+(int) (.025*ja);
}
return jul;
}